Electrical cord plug



Feb. 3, 1948. l c. w. cRuMRlNl-z 2,435,341

ELECTRICAL oo RD PLUG Filed Nov. 27, 1946 /f /5 252234+ v27 2'5 39 /6 U//f' ZZ' `mvENTcR Chester W Cru/77777@ ATTORNEYS Patented Feb. 3, 1948 ELECTRICAL CORD PLUG Chester W. Crumrine, Rochester, N. Y., assignor to Product Technicians, Inc., Rochester, N. Y.

Appxicatidnnovember 27, 1946, serial No. 712,705

7 claims. 1

This invention relates to electrical connectors and particularly to connectors of the class generally referred to as electrical cord plugs.

Devices of this class in the prior art generally comprise a body element into which a ilexible electrical cord enters and wherein the two conductors of the cord are connected by screw means with prongs which project from the body member for insertion in a usual electric outlet of well known form.

According to the present invention a-plug is provided wherein complete assembly or disassembly is effected by a single manipulation without the aid of a screw driver or any other tool. Further, the plug of the present invention is characterized by the fact that only four total parts are employed; the body element itself, a cover element, and the pair of metal conducting prongs. In place of the usual terminal screws for securing the copper leads of the electrical cord, the device of the present invention provides cam means which automatically secure both wires of the cord with the same movement which locks the cover to the body of the plug. By the same token, the usual screws used for holding the body parts of an electrical plug are eliminated in the present construction.

A single specific embodiment oi the principles of the present invention is illustrated in the accompanying drawing, but it is to be understood that the form there set forth is by way of eX- ample only and that the scope of the invention is not limited excepting as defined in the appended claims.

In the drawing:

Fig. l is a top plan View of one form of the cord plug of the present invention with a portion of the cover thereof shown in cross-section;

Fig. 2 is a bottom plan View of the cord plug of Fig. l;

Fig. 3 is a cross-sectional view on the line III-III of Fig. 1, but with the cover element in assembled position thereon;

Fig. 4 is a cross-sectional view on the line IV-IV of Fig. l, likewise with the cover element assembled thereon;

Fig. 5 is a perspective View of the body element of the device of Figs'. l through 4; and

Fig. 6 is a perspective view of the cover element therefor.

In the drawing, like characters of reference denote like parts and the numeral I3 designates generally a body element of insulating material having a well portion II formed therein. In the illustrated form, body element I0 is generally oblong and at one end thereof is provided with a notch I2 to receive the insulated portions of a pair of conventional electric conductor cords I3.

At the side opposite notch I2, body element I0 is provided with a pair of spaced parallel slots I4 and I5 which are proportioned to receive the medial portions of a pair of conducting prong elements I6 and I1. The bottom edges of prongs I1 and I8 are notched to lock over the bottoms of slots I5 and I6 as indicated at I8 in Fig. 4.

The inner ends of prongs I6 and I1 are provided with openings I9 and 20 and in assembling the cord plug being described, copper leads 22 and 23 of the conductors I3 are drawn through the respective openings I9 and 28 of prongs I3 and I1. Thereupon, the prongs are disposed in assembled position in the slots I4 and I5 and ledges 24 and 25 formed in well II adjacent to notch I2 support the inner ends of the prongs. The knotting of the conductors I3 indicated at 21 in Figs. 1 and 4 prevents pulling the cord outwardly of body element I0 by abutment against the edges of notch I2.

Following this simple assembly step, the device is ready for final locking which is accomplished by the association therewith of a cover member 30 which is generally ilat and preferably of the same contour as the body element I0. Cover element 30 has projecting centrally therefrom a cam portion 32, a reduced circular neck 33 and an oblong terminal enlargement 34, which, in the illustrated instance has arcuate beveled ends 35 and 3S. At the bottom of well II, body member I0 is provided with a pair of facing louvres 31 proportioned and spaced to receive the enlargement 34 therebetween so that cover element may be placed downwardly over the top of body member II) with enlargement 34 extending lengthwise between louvres 31. A subsequent quarter turn of cover element 30 moves the enlargement to the position illustrated in Fig. 3 and locks the cover element with respect to body member I0 by engagement of the beveled ends 35 and 36 of enlargement 34 beneath the overhanging edges of louvres 31.

The same movement, clockwise as viewed in Fig. 1, causes the cam formation 32, whose contour is best illustrated in Fig. l, to engage against the adjacent portions of the conductors 22 and 23. Note that the inner ends of prongs I6 and I1 bear laterally against ledges 38 and 39 formed in well II of body element III. The proportions of the parts are such that the prongs I1 and I8 are slightly exed apart by the cam 32 during closing movement of cover element 30. and the vices of this class, wherein the body elementsare` variously threaded and tapped. Also,-the locking A pressures engendered are inherent `'int-hefde'signoifw the device and not subject'tof'the discretioxr'or lack of discretion of unskilled fpersons: applying excessive screw driver forces and the like.` These considerations permit the employmentofa wider* range of choice of insulating material in the man- 20 ufactu're of. the body member'. 'i0 `and 'coverelement 13R. I

What isclaimed" is t i l... In an .electricalcordxpluggz'a :body .member havinga .Well formed inzone surfacefthere'oza 25's groove fin'. said surface; eXterrding-betweenrfsaid well and' the outermargin of 1: tlfrewbody jm'ember forerec'e'rvinga two-wire electrical acord,;a pairrof space d. groovesY likewise .extending between :said well .andthe outer ofA the 1 body member 230 and a pair ofplates ofconducting material' disposed` therein, said :plates fprojeictingsattheir inner ends' intoisaidy well ande at their outer ends outwardly. of said body member :for :engagement with an 'electrical 'outletrzeachosaid plates. havvv-35- ing 'ani .opening therethrough. adjacent its' inner end whereby the end of one ofthe wiresaofssaid cord may: be threaded therethrough; and; a `cover element adapted to seat.againstesaiob surface: of

said bodymember, s interlocking. meansfin.:the#.40V

bottom of the well of saidbody member, and said cover member having meansL interlockablezwith said interlocking means; byfffrelativefc turning movement of the body member and' tlrieic'overele ment with the'coverel'ement againstfsaid surface;y 45 and saidxcover element'havin-g.- a cam portion-fior acting against said platesrumm/interlocking a movement of said-parts for; clamping'- the-wires thereagainst. 2. "In an el'ectricalcord' plugtga .bodynmemberm having a wellY formed in-.oneesurfabethereofi:a groove in sai-dsurfa-ce extending between saiolwell and the outer'margin of :the.bodyimember'forzreceiving a two-wire electrical`v condea pair of' spaced grooves likewise extending between-.said well4 and :255 the outer margin of therbodyv member and' a. :pai-r of. plates Aof conductingmaiterialdisposedtlrerein, said .plates projecting at their? innerwendsdnto saidwell and at;their'louterendsioutwardlyxof said body-member for'engagemen-t with anzelec-vO trical outlet; each of.- said platesbeing gengageable adjacent .itsfinner'end :with toneof. ther wires of said cord, anda covervelementadaptedfsto seat. aga-instsaid surface. of l said; body?r member, interlocking means-in the bottomomhawenfefr sai-dbody member, and said. cover-member .having means interlockable with saidinterlocking means by.`V relative turning movementof. the .body-:member andthe coverelement with the cover-telemen-t against said surfacegandsaida cover-element hav-11.70 ingacam .portion forl acting against-said wires upon interlocking movement 'ofesaid-.partsi for clamping .the wires against thenplatea f 3..:In. an electrical. cord .p111g:arbody;member having a centraly well. rformed ein, vone :surface #75 thereof, a groove in said surface extending between said Well and the outer margin of the body member for receiving a two-Wire electrical cord, a pair of spaced grooves likewise extending between said well and the outer margin of the body member and a pair of plates of conducting material disposed therein, said plates projecting at their inner ends into said well and at their outerzends outyizardlyV of- 'said body member for engagement#with ari/'electrical outlet, each of g said plates having an opening therethrough adjacent its inner end whereby the end of one of the-wires ,of said cord may be threaded therethrough; and a cover Ielement adapted to seat against-saldi surfac'eof said body member, a pair -oiropposedi-fsocket `openings in the bottom of central -well of. said body member, and said cover member havingv means interlockable in said socketbpenings by relative turning movement of the body member and the cover element with the cover elementagainstsaidsurfaceyand said cover element havingza camportionorfactingfagainst said plates uponsinterlocking. movement= of said partsv for -clampingthe-wires' thereagainste 4. .-In. arr. electricalncord-plug, a body member having a. central. well...forrned..in. one. .surface thereom. a groove. incsaid; surface. extendingvbetween said wellandthe outermarg-in. of-thebody member for receiving. a two-wire electricalcord, a pair of spaced grooves likewise extending-.between said well and the-outer. margin of thebody memberand-a .pai-r of plates .ot :conducting material. disposed therein,-v .said plates projecting, :at their inner ends vintosaid. well andoat. theiroutzer ends outwardlyot said. body. member -forengagement .with an. electricaloutlet,- each .of said plates having ...an open-ing.. therethrough. adjacent Iits inner. endwhereby the end. of-:one-oi thewi-res of said` .cord may bethreaded .therethrough.,. .and-a .cover elementfadapted to seatagainstsaid sui.-

turning.V movement f of. the body member. and .the

cover Yelement Iwithxthe. cover .element .against said surface, said' cover element having-a.V cam portionv .for acting. against said. plates upon. interlocking movement .of said. partsl'or.. clamping. the

.Wires threagain'st, said cover. member. having .a

portion projecting.' toward the. body .member and adapted'. to come into. registry `withlancl.shan into one ofsaid grooves whenthe interlockingmeans and the cam means reach their n'alassembled positions.

5. In anelectrical..c0rd..plug, a. body member havinga .centraL Well. formedLir-i. one :surface thereof,- a .groove in said..,surface. extendingabetween said well andx theouter marginot the. body member for receiving a two-wire electrical cord, a fpairof. spaced groveslikewise .extending.;be tweensaid .Welland theioutei'. margin of tl'reb'ody member and a pair of plates-fof. conelnctingfmate- Y rial .disposed .thereinfsaid .plates .projecting at their inner. ends into said well:and.at theirouter `incrementi of@ theebody memberziandhtlreccover element with the cover element against said surface, said cover element having a cam portion for acting against said wires upon interlocking movement of said parts for clamping the wires against the plates, said cover member having a portion projecting toward the body member and adapted to come into registry with and snap into one of said grooves when the interlocking means and the cam means reach their nal assembled positions.

6. In an electrical cord plug, a body member having a central well formed in one surface thereof, a groove in said surface extending between said well and the outer margin of the body member for receiving a two-wire electrical cord, a pair of spaced grooves likewise extending between said well and the outer margin of the body member and a pair of plates of conducting material disposed therein, said plates projecting at their inner ends into said well and at their outer ends outwardly of said body member for engage ment with an electrical outlet, each of said plates having an opening therethrough adjacent its inner end whereby the end o f one of the Wires of Said cord may be threaded therethrough, and a l cover element adapted to seat against said surface of said body member, interlocking means in the bottom of the central well of said body member, and said cover member having means interlockable with said interlocking means by relative turning movement of the body member and the cover element with the cover element against said surface, and said cover element having a cam portion for acting against said plates upon interlocking movement of said parts for clamping the wires thereagainst, said cover member having a, portion projecting toward the body member and adapted to come into registry with and snap into said cord receiving groove when the interlocking means and the cam means reach their nal assembled positions.

7. In an electrical cord` plug, a body member having a central well formed in one surface thereof, a groove in said surface extending between said well and the outer margin of the body member for receiving a two-Wire electrical cord, a pair of spaced grooves likewise extending between said well and the outer margin of the body member and a pair of plates of conducting material disposed therein, said plates projecting at their inner ends into said well and at theirouter ends outwardly of said body member for engagement with an electrical outlet, each of said plates being engageable adjacent its inner end with one of the wires of said cord, and a cover element adapted to seat against said surface of said body member, interlocking means in the bottom of the central well of said body member, and said cover member having means interlockable with said interlocking means by relative turning movement of the body member and the cover element with the cover element against said surface, and said cover element having a cam portion for acting against said wires upon interlocking movement of said parts for clamping the wires against the plates, said cover member having a portion projecting toward 'the body member and adapted to come into registry with and snap into one of said grooves to retain the interlocking means and the cam means in nal assembled position.

CHESTER W. CRUMRINE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,645,650 Kirkman Oct. 18, 1927 2,217,585 Yates Oct. 8, 1940 2,097,603 Ruth Nov. 2, 1937 

